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1 <br />' The lowest chord of the conveyor bridge will be at least three feet above the effective base <br />' flood elevation (BFE, 100 year water surface elevation) as required by UD&FCD through <br />Adams County. The bridge approach ramps will come down from the bridge at 2% to 5% <br />grades on each side of the river. Temporary overburden and topsoil stockpiles will be placed <br />' parallel to the overbank flow direction of the River and will have a maximum height of 20' and <br />base width of 100'. The stockpiles will be limited to 300' in length, with minimum 100' gaps <br />between, to avoid levee type floodplain constrictions (CS#1). <br />Agreement with UD&FCD will be necessary on river stabilization improvements required to <br />mine within 400' of the river banks (CS#12) Other activities within the regulatory <br />' floodplain, such as emergency overflow areas at reasonable intervals in the reservoir banks, <br />will require issuance of a Floodplain Use Permit (CCP#12). The Floodplain Use Permit <br />application will include a hydraulic analysis of the S. Platte River to evaluate the proposed <br />' floodplain features created in the mining. The preliminary findings of the hydraulic analysis <br />indicates no rise in the floodplain effective BFE's due to the conveyor bridge, bridge <br />approaches, and overburden stockpiles, which is in conformance with Adams County <br />requirements (CCP#12). <br />' Surface Water <br />The mining operation is adjacent to the Fulton Ditch as shown on Exhibit C-1, Pre-Mining <br />t Map, Exhibit C-2, Mining Plan Map, and Exhibit F, Reclamation Plan Map. The proposed <br />mining operation will setback a minimum of 50' from the edge of the outside ditch bank. The <br />perimeter of the ditch will lie adjacent to active mining for approximately 2,800'. The Fulton <br />' Ditch will not be disturbed during the mining and reclamation operations. However, the <br />groundwater lake elevation will not be different from historic levels because no dewatering <br />is proposed. <br />' The Spring Creek Seep Ditch from the Bull Seep feeds into the Fulton Ditch just downstream <br />of the head gate. Although there is no specific water rights attached to this seep, it is <br />recognized as a source of supply to the Fulton Ditch. The length of the seep ditch passing <br />through the permit area is 1,300 linear feet. There will be no mining in the area of the seep <br />and it is not expected to be adversely impacted by the operation. <br />' There are some minor ditch laterals on the CAMAS property to the west of the river that will <br />be relocated during the mining process. There are no water rights associated with these <br />laterals and appear to only serve for returning tail water to the river from adjacent imgated <br />fields. The ditches will be rerouted around the mining area to maintain drainage across the <br />' property. Such routing will be in conformance with a Final Drainage Plan to be submitted and <br />approved by Adams County (CCP#13). Such Final Drainage Plan shall include addressing <br />the drainage channel that presently exists along McKay Road in a defined easement large <br />enough to accommodate flow and maintenance access (CCP#13) . <br />' 2 <br />1 <br />